Dental engine.



0. H. & A. F. PIEPER.

DENTAL ENGINE.

APPLICATION FILED MAILZ, 1910.

1,040,576. Patented 001;. s, 1912.

2 sums-81mm 1.

ym; 1 aqwsnm 0. H. & A. F. PIEPER.

DENTAL ENGINE.

APPLICATION TILED MAR. z, 1910.

1,040,576. Patented Oct. 8, 1912.

2 SHEETSSHEET 2.

ZM/ 35 w UNI D" STATES PATENT OFFICE.

OSCAR H. tPIEP-ER AND ALPHONSE F. PIEPER, 0F RQCHESTER, NEW YORK,

DENTAL ENGINE.

Speciflcation of Letters Patent.

Application filed March 2, 1910. Serial No- 546,768.

To all whomz'tm'a concern:

Be itv known t at we, OSQAR H. Pmren and ALPHONSE F. PJEPER, both of thecity of Rochester, county of Monroe, and State of New York, haveinvented certain new and useful Improvements in Dental Engines; and wedo hereby declare the following to be a full, clear, and exactdescription of the same, reference being had to the accompanyingdrawings, forming a part of this specification, and to thereferencenumerals markedthereon.-

The present invention relates to dental engines and it has for anobjectto provide av construction in which the motor. is so arrangedthat. it acts as a counterbalance for the supporting arm, while at thesame time fitsweight. is so disposed that it does not interfere with theturning of the supporting arni about a vertical axis. a

f Another object of the invention is to provide .an -improved-supporting arm formed ofielescopingmembers so constructed thatbinding. action between the members, interfering with-their freeoperation, is obviated.

To' these and other ends the invention con.- sists in certainimprovements and combinations of parts all as will be hereinafter morefully/described, the novel features being pointedout in the claims atthe end of the specification.

In' the drawings: Figure 1 1s a side view of. .the en 'ne with thesupporting arm thereof ralsed to its uppermost position; Fig. 2 is adetail top view of the engine with the supporting arm partially brokenaway; Fig. 3 is. an'enlarged side view of the engine with parts invertical section, apart of the supporting arm being removed Fig. .t-is'adetail View of the supporting arm in proximity to the joint between itsmembers;

Fig. 5 is asection on the line aa of Figg i;

Fig. 6 is a section on the line bb of 4; Fig. 7 is a section on the line0-0 of Fig. 4; Figs. 8 and,9 are vertical sections of the bufferemployed for retarding the motor or counterbalance near the latterart ofits :movement; Fi 8 being a sectlon-on the line al--d of Fig. 9, andFig.9 being a sec taching member or bracket 1- aving; upper other andlower arms 2 on which turns aframe 3, removable bearings 4 for thispurpose being provided on the arms 2 to cotiperate with bearing recessesin the frame 3 so that the latter may swingabout the vertical axis. Theframe 3 is provided with a pair of parallel arms 5 between which ispivoted fat 6 on a horizontal axis the supporting arm ior member of theengine. The supporting larm in this instance comprises apivot memlber 7formed of a single castin lvided at one side with. a shoul er 8 .fromfwhich projects integral pins or projections 39. These pins orprojections are detachably engaged by the inner end of the inner memberof the supporting arm, the latter pref- {erably comprlsing two tubularrods 10 fitted {over the rojections 9 and connected at their ginner en sb a member or plate 11 which has two hol ow bosses 12 secured thereto{and to the tubular rods 10. The plate 11 rests against the shoulder 8and is held ,in such a position by any suitable means. In the presentinstance a thumb screw 13 passes through the plate 11 and engages screwthreads on the walls of the opening 14 in the pivot member 7.

The outer ends of the tubular rods 10 are preferably connected by amember 15 in the'form of a yoke provided with a guide having taperingwal s 17 and its axis extending in a line between the rods 10 to receivethe outer member 16 of the supporting arm. Fitted within this openingand about ,the member or rod 16 is a sleeve 18 split at 19 and havingits inner ends tapered to.

packing ring 21 into engagement with the tubular rod 16. The innerdiameter of the sleeve 18 is much larger than the external diameter ofthe tubular rod 16 so that the latter lies in spaced relation to theinner walls of the sleeve and the nickle lating or olished surface ofthetubu lar rod is not a ected by the telesco ing movement. Arranged toengage the en of thetubular rod 16, there is provideda member 22 hav--Patented Oct. 8, 1912..

and proing an exteriorly threaded boss 23 fitting the rod 16. Thismember may carry two guides 24 through which the rods 10 travel, and theguides 24 are provided with pockets 25 to receive packing which preventsthe abrasion of the surface of the tubes 10, jam nuts or bushings 26holding the packing in position.

At the outer end of the member 16 is provided a pendant arm 27 carryinga handpiece connecting-arm 28 which has at its outer end the hand-piece29. The latter is driven by an endless cable 30 which passes from apulley on the shaft of the motor 31, (supported in a manner to behereinafter described) over pulleys 32 supported in rear of the turningaxis 6 on arms '33 lying on the outside of the frame arms 5; one strandof the cable passing directly to one of the pulleys 34 at the outer endof the supporting arm, thence to one of. the pulleys 35 to the toolpulley 36; the other strand passing about a pulley 37 on the innermember 10, thence about a pulley 38 on the inner end of rod 16 and thensuccessively to the. pulley 34, the pulley 35 and the pulley 36, thisarrangement permitting the telescoping of the supporting arm whilemaintaining the driven cable taut. The pulley 37 is pref erabl supportedon one side of the bracket 39 W ich surrounds the rods 10 and 16 and Iis held to the rods 10 by a clamping screw40,

. end the frame 3, on which-the motor is sup a retaining device 41 beingprovided on the bracket 39 to prevent the cable leaving the pulley. Thepulley 38 is supported on one side of the rod supporting member 22,-the'cable being retained on the latter by a guard 42 pivoted at 43 andyieldingly held in either of two positions by a spring pressed ball 44entering notches in the guard 42.

The motor for driving the "hand piece is preferably movable verticallyand to this ported, is of yoke formation, its arms being provided ontheir opposed faces with guideways 45 receiving guide projections 46which, in this instance, are resilientlysupported in soft rubber cups 47from themotor, the resilient cups acting as insulators andpreventingt-he vibrations of the motor being transmitted to the frame 3.

In. order that the. motor may counter balance the supporting armconnectionbetween the latter and said motor is provided. Preferably thisconnection is in the'formof a sector-shaped or segmental rack 48 formedintegral with the pivot member 7 and meshing with a straight rack 49which is resiliently connected to the motor 31 byasoft rubber thimble50, also serving as an insulator betweenthese parts, he the supportin'garm approach s a" vertical pos tion,

I h w in Fig.1, it exerts a constantly do creasing resistance to theaction of the n un terbalalnce'oiifmotor, and after it has-passed teatre lid on the swinging frame 3 between the arms I 5 of the latter.The abutment 51 normally lies in engagement with the stop 55 being heldthereagainst by a spring which, in this instance, is in the form of atrue spiral 56 arranged within the drum 54 and having 7' one end securedat 57 to the drum and the other end secured to the sleeve 58. The latteris rotatable in. the side walls of the drum and is supported upon a pinor bolt 59 which connects the arms 5 of the frame 3. The bolt 59 ispreferably provided with a longitudinal slot receiving a pin 60 in thesleeve '58 to hold the latter-against rotation, the bolt in turn beingheld against rotation by a pin 61 secured to the frame 3 and receivedalso within the slot. It is apparent thatathe bolt 59 may be withdrawnout of engagement with the pin 51 and rota to'turn the sleeve 59 in,order that the tension'of the Es'prin 56 may be varied the pin 61serving :to ho d the bolt in its 2M? position.

g The operation of the'engine be apparent to those familiar with thesemachines,

but it may be stated generally that the new :ing of the supporting arm'edects, throu h the racks. 48 and 49,.the elevation of t e motor 31which soacts on the arm to coun:

terbalance the latter. .Qf' coursewhen the supporting arm is lowered thehand piece,

through the arms 27- and 28, ma assume any position, the turning of'theame- 3' also assisting in .thepositloni-ng. en the su jpo'r'tlng armisagain moved upwardly, t e

abutment 52, toward the latter part of the downward movement of themotor, engages the abutment 51 onthe retarding device. or; mg

suddenly to an upright osition; itl'being,

apparent that the lighter ecomes the ede'ct' .bufier, thus preventingthe bei-n 'moved of the arm the greater becomes the "cushion;

efiect of .the buffer so that the'counter- [-ba ancing efiect is stillmaintained. From the foregoing it will be seen" that there has beenrovided a supporting arm 1n which the frictional contact between the twotelescoping members has beenreduced' to a minimum so that the chancesofbinding have also been reduced. The motor isso po-:

its

lsitioned that the machine does'not-require agreatdeal of space,forinstallationand the 1 weight of the .motor is so disposed that "itdocs not'materlally afiect the turningpfthe turn on the frame about ahorizontal axis, a

hand piece carried by the supporting arm, a counter-balance mounted insaid frame, means carried by the counter-balance havingpositiveengagement with the supporting arm, and means for guiding thecounterbalance vertically in the frame.

2. In a dental engine, the combination with a frame mounted to turnabout a vertical axis, of a supporting arm mounted to turn about ahorizontal axis on the frame, a

hand piece on the arm, a counterbalance mounted in the frame, meansguiding the counter-balance vertically on the frame, a sector shapedrack on the arm concentric with the axis, of the latter,

- rack on the counterbalance meshing with the sector-shaped rack.

3. In a dental engine, the combination with a frame mounted to turnabout a vertical axis and provided with vertical guideways, of asupportin arm mounted to turn about a horizontal axis on the frame, ahand piece on'the arm, a motor for driving the hand piece, guideprojections resiliently carried by the motor and 0 crating in the vertical guideways of the rame, driving connection between the motor andthe hand piece, and means operativel connecting the motor and the armwhere y the latter is counterbalanced by the former.

i. In a dental engine, the combination with a frame mounted to turnabout a vertical axis, of a supporting arm mounted to swing about ahorizontal axis onthe frame,

a hand piece supported b the arm, a mo-' tor vertically movable on t eframe for driving the hand piece, a sector-shapedv rack on the armconcentric with the axis of turning of the latter, a straight rackresiliently connected to the motor, and a driving connection leadingfrom the motor and connected to the hand piece. 1

5. In a dental engine, the combination with a yoked frame havingguideways on its arms and mounted to turnabout a vertical axis, of anarm mounted to swing onthe frame about a horizontal axis, a hand iecesupported by the arm, a motor for the hand piece mounted in said frame,guide projections resiliently carr ed by opposite sides of the motor andcooperating with the 'uideways on the frame so that the motor is alinedwith the axis of turning of the frame, a sector-shaped rack on the arm,a

straight rack on the motor resiliently conand a straight therefor, of aleading from the motor to the hand piece,

"member driving nected to the latter, and a driving connec tion leadingfrom the motor and connected to the hand piece. a

6. In a dental engine, the combination with a frame, of a supporting armmounted to turn about a horizontal axis on the frame, a hand piececarried by the supporting arm, a motor slidably mounted upon the frameand having a connection with the supporting arm whereby tocounter-balance the same, and driving connections between the motor andthe hand piece.

7. In a dental engine, the combination with a hand piece and asupporting a'rm therefor, of a motor, means for guiding the motorvertically, counter-balancing connections between the motor and thesupporting arm, a driving cable leading from the motor and connected tothe hand piece, and a pair of pulleys located in the rear of the turningaxis of the arm and having the driving cable passing thereovertoward'and from the hand piece.

8. In a dental engine, the combination with a supporting arm mounted toturn about a horizontal axis, of a hand piece carried by the arm, amotor for driving the hand piece mounted in the frame for verticalmovement and having connection with the supporting arm whereby tocounter-balance the latter, an elastic buffer for retarding the movementof the latter, and a driving connection leading from the motor to thehand piece.

9. In a dental engine, the combination with a hand piece and asupporting arm therefor, of a motor, a driving connection leading fromthe motor to the hand piece, the supporting arm embodying a pivotedmember having projections extendingtherefrom, a member formed of tubesfitting the projections, a plate connecting the tubes, and means forsecuring the plate to the pivoted member.

10. In a dental engine, the combination with. a hand piece and asupporting arm motor, a driving connection the supporting arm embodyinga pivoted having projections extending therefrom and a shoulder at thebase of the proections, of a member comprising two tubes fitted to the(projections, a plate connecting the tubes an abutting the shoulder, anda screw for holding. the plate against the shoulder; r j i 11. In adental engine, the combination with a hand piece and a supporting armtherefor, of a motor, a driving connection leading from the motor to thehand piece,

the supporting arm embodying an inner member including a pair of rods, aconnecting device at the'outer ends of the rods, an outer memberarranged for movement in the connecting device and having guiding meansi eee ete end e, pecking ring held by the split eieeve end eomphessedupon the test mentioned memhei' hy the tapered Wells.

13.. In it dentei engine the comhinetien with e frame monnmd to tuneehent e V1T- mentioned member and entieei axis of e supporting memounted to turn on the theme about t horizontal exis e. hand pieeecarried by the supporting am, it counterhaience mounted 1n the frame,means operatively connecting the counterbalance with the supporting armeomprising-e curved toothed surface on ene of the parts in engagementwith e correspondingly toothed plane surface on the other part, and Vmeens for guiding the counter-balance ver- I tieeiiy in the frame.

@SCAR H. PIEPER. ALPHQNSE F. PIEPER.

Witnesses:

Rneenm B. Gent-"me LUCY A, VAN Count,

